State regulators have suspended the license of an Edina dentist whose teenage patient died last June after a procedure to have her wisdom teeth removed.

Sydney Galleger, a junior at Eden Prairie High School, went into convulsions during the June 9 surgery and was rushed to a hospital, where she died.

The Minnesota Board of Dentistry cited "imminent risk of harm" in its order against Dr. Paul Tompach of Edina Oral and Maxillofacial Surgery.

The order said the board "received credible information" that Tompach "failed to appropriately manage a medical emergency, and enabled medical personnel (i.e., an unlicensed dental assistant, licensed dental assistant, and student intern) to perform tasks which exceeded the legal scope of practice."

Bridgett Anderson, the board's executive director, said Monday that Tompach allowed a dental assistant who lacked the state-required course work and certification to monitor the teen as she received anesthesia.

Contacted by telephone Monday morning, Tompach said, "I'm not taking calls," and hung up.

License suspensions against Minnesota dentists are unusual: The board has issued about three to six annually in recent years.

Overall, the dentistry board took 70 disciplinary actions against dentists, dental assistants and dental hygienists in the two-year period ending June 30, 2014, but most were "corrective actions" ordering changes in professional practice or training.

The board will convene in private Thursday and vote on a final stipulation to which investigators and Tompach have agreed.

Anderson declined to reveal what that agreement includes. She also could not say whether the board is reviewing the dental assistant's actions.

Student was diver, skier

Sydney's father, Steve Galleger, said Monday the family was unaware of the suspension order and declined to comment. "This is all new to us," he said.

Sydney Galleger, a diver on the school swim team and an Alpine skier, went to Tompach's Edina offices on June 9. On June 15, Galleger's family announced her death on a CaringBridge page.

Diane Galleger explained on CaringBridge that everything was going well with the procedure "until the very end, when her blood pressure shot up and her pulse dropped and then she went into cardiac arrest."

She said Tompach started CPR and called 911 when the convulsions began.

Paramedics quickly arrived and got Galleger to a hospital. Once at the University of Minnesota Masonic Children's Hospital, she was stabilized but continued to have seizures, Diane Galleger wrote.

In September, the Hennepin County medical examiner's office ruled that Galleger suffered cardiac arrest but said the cause "is undetermined." The medical examiner added that medication she was receiving at the time "could not be excluded" as playing a role in her death.

'The perfect storm'

In a follow-up posting after the autopsy, Diane Galleger described the incident as " 'the perfect storm.' Sydney had a slight abnormality in her heart and signs of a viral infection on her brain. None on their own was felt to be enough to cause a cardiac arrest. Could she have had a slight reaction to the medications causing everything to misfire? Unlikely, but we will never know."

According to his business Web page, Tompach is the only dentist on staff at the Edina Oral office.

He received his dental degree from the University of Minnesota and completed his residency in oral and maxillofacial surgery at the University of Iowa and also completed a surgery fellowship at Harvard University and Massachusetts General Hospital.

Tompach also performs Botox injections and other cosmetic procedures as part of his Edina Facial Aesthetic Specialist practice. Anderson, who directs the dentistry board that also has jurisdiction over facial cosmetic procedures, said the fate of that part of Tompach's profession will be addressed in Thursday's final order.

Anderson said Tompach's case took longer than other investigations "due to the complexity" of the circumstances and coordinating with different agencies.

"The data collection alone does take time," she said. "The medical examiner's report was very important."

Board records show no other disciplinary actions in Minnesota against Tompach, but he settled a malpractice lawsuit in 1999 involving the removal of a patient's teeth.

LeRoy Ericson, now 82, went to Tompach to have some teeth extracted to make way for partials, but "he took all of them, instead of some of them," said Mildred Ericson, speaking for her husband because he has difficulty hearing.

Neither Mildred nor LeRoy Ericson remember Tompach explaining what happened. "I think he just made a mistake is what it amounted to," she said.

The two sides settled the suit for an amount Mildred Ericson could not recall, but "it ended up to be enough so LeRoy could buy a new truck."

Star Tribune staff writer Glenn Howatt contributed to this report. Paul Walsh • 612-673-4482